Archaeological Investigations Along Reach 4 of the Granite Reef Aqueduct, Central Arizona Project

Under contract with the Bureau of Reclamation, the Office of Cultural Resource Management (OCRM), Department of Anthropology, Arizona State University, completed archaeological survey of Reach 4 and several access roads that would be modified for its construction. Reach 4 of the Granite Reef Aqueduct extends about 14 miles from the Hovatter Road exchange with Interstate 10 to the Centennial Wash Siphon Outlet.

OCRM archaeologists identified and documented 22 field loci, 200 isolated artifacts, and 3 areas of historic trash during the Reach 4 survey. Based on relative density of cultural material dispersion, 19 of the field loci and the majority of the isolated artifacts were grouped into a single site, AZ S:7:13 (ASU).

Mitigation was completed at AZ S:7:13 (ASU) in August 1979. AZ S:7:13 (ASU) is an extensive artifact scatter covering 1288 .6 acres. Within this area are varying densities of chipped stone artifacts, ground stone, and ceramics. Four areas of high artifact density were designated as Components A through D. Sample units measuring 50 X 10 meters were placed in areas of varying artifact density, and artifacts were surface collected in one square meter grids within the sample units. Eleven test pits were also excavated, four within rock concentrations. One feature, approximately 25 cm in diameter, was identified. It consisted of a ground stone slab at the base of a small pit.

The investigations identified a pattern of secondary resource zone exploitation in the desert areas between the river valleys. Researchers defined and described a secondary resource zone as an area which did not support a permanent population, but was utilized intermittently, probably on a seasonal basis, in the exploitation of wild plant and animal food resources by people whose primary subsistence was derived from a different zone.